The present invention relates to a hydraulically driven type working machine, and more particularly to a hydraulic pipe arrangement mechanism of a hydraulically driven excavation working machine equipped in construction machinery.
A hydraulically driven excavation working machine equipped in construction machinary such as an excavator or the like is structured such that members such as a boom, an arm, a bucket and the like are connected in series in accordance with this order from a machine main body so as to freely bend with each other. In order to supply an oil pressure to a hydraulic actuator for operating these members, there is used a hydraulic pipe arrangement apparatus for arranging a hydraulic hose from a side of a machine frame along outer portions or inner portions of the boom and the arm.
However, the conventional hydraulic pipe arrangement apparatus mentioned above has the following problems.
If it is desired to insert the hydraulic pipe arrangement in the side of the machine frame into the inner portion of the boom from a base portion of the boom over a boom hoisting supporting point pin or to insert the hydraulic pipe arrangement installed within the boom into the inner portion of the arm over a joint connection supporting point pin of the arm, it is impossible to apply a slack to the hydraulic pipe arrangement in the portion over the supporting point pins. Accordingly, due to a hoisting swing motion of the boom and a bending swing motion of the arm, the hydraulic pipe arrangement is in contact with the boom hoisting supporting point pin or the joint connection supporting point pin of the arm so as to be bent, thereby damaging the hydraulic pipe arrangement. Accordingly, the structure has been conventionally made such that these hydraulic pipe arrangements have been executed so as to extend along the outer portions of the boom and the arm, or a hole is provided in a wall of the boom and the hydraulic pipe arrangements are inserted into the inner portion of the boom, so that it has been hard to execute the hydraulic pipe arrangements in the inner portions of the boom and the arm without exposing them to the outer portion of the boom and the arm.
Further, in the hydraulic pipe arrangement to a hydraulic actuator for driving a boom hoisting operation, the actuator swings tilting in a longitudinal direction. Accordingly, a slack is provided in the hydraulic pipe arrangement extended to the actuator from the side of the machine frame, and it is impossible to extend to the actuator from the side of the machine frame without slacking the hydraulic pipe arrangement.
Further, the hydraulic pipe arrangements connected to the hydraulic actuator for driving the boom hoisting operation, the hydraulic actuator for driving the arm bending operation and the hydraulic actuator for driving a working tool are all provided with pipe arrangement connecting devices exposing to the outer portions of these actuators, and it is hard to execute the hydraulic pipe arrangements so that the hydraulic pipe arrangements of the respective actuators are not seen from an outer appearance of the working machine.
The present invention is made by paying attention to the problems in the conventional art mentioned above, and an object of the present invention is to provide a hydraulically driven type working machine in which a rotary joint of a hydraulic pipe arrangement is provided in a boom hoisting supporting point and an arm joint connection supporting point, whereby a pipe arrangement can be installed in inner portions of a boom and an arm without applying a slack to the hydraulic pipe arrangement, the rotary joint of the hydraulic pipe arrangement is provided in a hoisting supporting point of a hydraulic actuator for driving a boom hoisting operation, whereby the pipe arrangement can be executed in the hydraulic actuator for driving the boom hoisting operation without slacking the hydraulic pipe arrangement from a side of a machine frame, and fluid flow passages communicating with respective cylinder oil chambers are provided in inner portions of respective cylinder rods, in the hydraulic actuator for driving the boom hoisting operation, a hydraulic actuator for driving an arm bending operation and a hydraulic actuator for driving a working tool so as to form the respective actuators that the hydraulic pipe arrangements are not exposed, thereby making the hydraulic pipe arrangements invisible from an outer appearance of the working machine, together with an effect of installing the pipe arrangements in the inner portions of the boom and the arm.
In order to achieve the object mentioned above, in accordance with a first aspect of the present invention, there is provided a hydraulically driven type working machine comprises a boom having a vertical swing supporting point supported at a base end side by a machine frame and a joint connection supporting point in a front end side, an arm connected in a base end side to the joint connection supporting point of the boom, a boom driving hydraulic cylinder hoisting around a hoist supporting point provided in the machine frame so as to drive the boom, an arm driving hydraulic cylinder driving the arm and a working tool driving hydraulic cylinder driving a working tool mounted to an arm front end side,
wherein a swivel joint mechanism for relaying a hydraulic pipe arrangement from a side of the machine frame is provided at a center of at least one of the vertical swing supporting point, the joint connection supporting point and the boom driving hydraulic cylinder hoist supporting point.
In accordance with the first aspect, since at a time of pipe arrangement in the arm driving hydraulic cylinder and the working tool driving hydraulic cylinder, it is possible to execute a rotary joint pipe arrangement around the boom hoist supporting point by connecting a pipe arrangement extended from the side of the machine frame to one side hose joint of a swivel joint mechanism provided at the boom hoist supporting point and connecting a hydraulic cylinder side pipe arrangement extended along the boom side to another side hose joint rotating around the boom hoist supporting point, and it is not necessary to apply a slack to the hydraulic pipe arrangement between the side of the machine frame and the side of the swinging boom, it is possible to obtain an economical pipe arrangement, a durability of the hydraulic hose is improved due to no bending application to the pipe arrangement, and it is possible to correspond even to a narrow pipe arrangement space.
Further, in the pipe arrangement to the working device driving hydraulic cylinder extending to the arm via the boom, it is possible to execute the rotary joint pipe arrangement around the arm joint connection supporting point by connecting a pipe arrangement extended along the side of the boom to one side hose joint of the swivel joint mechanism at the center of the arm joint connection supporting point existing in a front end side of the boom and connecting a hydraulic cylinder side pipe arrangement extended along the arm side to another side hose joint rotating around the arm joint connection supporting point. Since it is not necessary to apply a slack to the hydraulic pipe arrangement between the boom and the arm bending with respect to the boom, it is possible to obtain an economical pipe arrangement, and a durability of the hydraulic hose is improved due to no bending application to the pipe arrangement.
Further, in the pipe arrangement from the side of the machine frame to the boom driving hydraulic cylinder, it is possible to execute the rotary joint pipe arrangement around the cylinder hoist supporting point by connecting the pipe arrangement extended from the side of the machine frame to one side hose joint of a swivel joint mechanism provided in the boom driving hydraulic cylinder hoist supporting point and connecting the pipe arrangement extended along the cylinder side to another side hose joint rotating around the cylinder hoist supporting point. Since it is not necessary to apply a slack to the hydraulic pipe arrangement between the machine frame side and the swinging cylinder side, it is possible to obtain an economical pipe arrangement and a durability of the hydraulic hose is improved due to no bending application to the pipe arrangement.
In accordance with a second aspect of the present invention, there is provided a hydraulically driven type working machine as recited in the first aspect, wherein the swivel joint mechanism has one side hose joint connected to the machine frame side and another side hose joint connected to the hydraulic cylinder side, and a hydraulic valve for shutting off at least one of a plurality of oil passages communicated another side hose joint with the hydraulic cylinder or restricting an area of the oil passages is provided in the oil passages.
In accordance with the second aspect of the present invention, since the oil passage to the hydraulic cylinder is shut off or the oil passage area is restricted at a time when another side hose joint is taken out for maintenance or the hydraulic pipe arrangement to the swivel joint mechanism is burst, the hydraulic cylinder does not suddenly expand or compress and the working machine does not drop down.
In accordance with a third aspect of the present invention, there is provided a hydraulically driven type working machine as recited in the first aspect, wherein the swivel joint mechanism at the center of the vertical swing supporting point of the boom is arranged between left and right divided supportng shaft pins of a forked boom swing supporting shaft portion, and is provided with one side hose joint of a pipe arrangement rotary joint concentric with a center of the supporting shaft pins connected to the machine frame side and another side hose joint connected to the boom side.
In accordance with the third aspect, since the swivel joint mechanism at the center of the boom vertical swing supporting point is arranged between the left and right divided supporting shaft pins of the forked boom swing supporting shaft portion, it is not necessary to secure a surplus arrangement space around the boom hoist supporting point. Further, since the swivel joint mechanism is arranged immediately below the boom and the hydraulic pipe arrangement is installed in the boom, whereby the pipe arrangement does not expose to an external portion from the immediately below portion of the boom, the swivel joint mechanism and the pipe arrangement are sufficiently protected.
In accordance with a fourth aspect of the present invention, there is provided a hydraulically driven type working machine as recited in the first aspect, wherein the swivel joint mechanism at the center of the joint connection supporting point of the arm is arranged between left and right divided supportng shaft pins of a forked arm joint connection supporting shaft portion, and is provided with one side hose joint of a pipe arrangement rotary joint concentric with a center of the supporting shaft pins connected to the boom side and another side hose joint connected to the arm side.
In accordance with the fourth aspect, since the swivel joint mechanism at the center of the arm joint connection supporting point is arranged between the left and right divided supporting shaft pins of the forked arm joint connection supporting shaft portion, the swivel joint mechanism does not expose to an external portion from a profile of the boom and the arm, thereby preventing damage.
In accordance with a fifth aspect of the present invention, there is provided a hydraulically driven type working machine as recited in the first aspect, wherein the swivel joint mechanism at the center of the boom driving hydraulic cylinder hoist supporting point is arranged close by a supporting shaft pin which is the hoist supporting point of the boom driving hydraulic cylinder, and is provided with one side hose joint of a pipe arrangement rotary joint concentric with a center the of supporting shaft pin connected to the machine frame side and another side hose joint connected to the boom driving hydraulic cylinder side.
In accordance with the fifth aspect of the present invention, the boom driving hydraulic cylinder hoist supporting point is a hoist supporting point of a boom driving hydraulic cylinder structures such as to connect a front end portion of a piston rod having oil passages respectively extending to a head side oil chamber and a bottom side oil chamber of the boom driving hydraulic cylinder to the side of the machine frame by a supporting shaft pin, and the swivel joint mechanism relaying the pipe arrangement to the boom driving hydraulic cylinder is arranged in the center of the hoist supporting point. Accordingly, the pipe arrangement of the boom driving hydraulic cylinder is supplied from one side hose joint rotating together with the hoist of this cylinder to the cylinder, and a length of the pipe arrangement can be significantly reduced in comparison with the conventional one.
In accordance with a sixth aspect of the present invention, there is provided a hydraulically driven type working machine as recited in the third aspect, wherein one side supporting shaft pin of the left and right divided supporting shaft pins in the boom swing supporting shaft portion has a connection flow passage connecting the machine frame side pipe arrangement to the swivel joint mechanism, the one side hose joint is a columnar joint having a pipe arrangement joint flow passage in the side of the machine frame mounted to an axial direction of the one side supporting shaft pin, the another side hose joint is a cylindrical joint fitted to the columnar joint and provided with a plurality of inner circumferential annular grooves communicated with the pipe arrangement joint flow passage of the columnar joint and respective through holes communicated with these inner circumferential annular grooves, a boom built-in pipe arrangement is mounted to the cylindrical joint, and the swivel joint mechanism is connected to the boom so that the cylindrical joint rotates together with the swing motion of the boom in a following manner.
In accordance with the sixth aspect of the present invention, since the structure is made such that the machine frame side pipe arrangement is taken in the lower side of the boom base end via the boom supporting shaft pin, it is not necessary to execute the pipe arrangement via the boom bracket, and it is possible to reduce the length of the pipe arrangement in comparison with the conventional one.
In accordance with a seventh aspect of the present invention, there is provided a hydraulically driven type working machine as recited in the fourth aspect, wherein the another side hose joint of the swivel joint mechanism at the center of the arm joint connection supporting point is constituted by a joint in which a pipe arrangement block and a columnar joint concentric with the center of the supporting shaft pin are integrally formed in an L shape so as to form an interior communication flow passage extending from the columnar joint to the pipe arrangement block, the one side hose joint is constituted by a cylindrical joint fitted to the columnar joint and provided with a plurality of inner circumferential annular grooves communicated with the interior communication flow passage and respective through holes communicated with these inner circumferential annular grooves, the cylindrical joint is connected to the boom side so as to form a connection joint of a boom built-in pipe arrangement, and the pipe arrangement block is mounted to the arm side so as to form a connection joint of an arm built-in pipe arrangement.
In accordance with the seventh aspect of the present invention, a plurality of internal communication passages in the columnar joint of the swivel joint mechanism at the center of the joint connection supporting point is communicated with a plurality of inner communication passages directed to the arm front end direction of the pipe arrangement block. Accordingly, since the direction of the pipe arrangement with respect to the working tool driving hydraulic cylinder is aligned so as to be directed to the front end of the arm, it is unnecessary to execute the pipe arrangement within the arm, the pipe arrangement is simplified, and an assembling property of the pipe arrangement is improved. Further, since the pipe arrangement is not exposed, a good appearance can be obtained.
In accordance with an eighth aspect of the present invention, there is provided a hydraulically driven type working machine as recited in the fifth aspect, wherein the another side hose joint of the swivel joint mechanism at the center of the boom driving hydraulic cylinder hoist supporting point is constituted by a joint in which a pipe arrangement block and a columnar joint concentric with the center of the supporting shaft pin are integrally formed in an L shape so as to form an interior communication flow passage extending from the columnar joint to the pipe arrangement block, the one side hose joint is constituted by a cylindrical joint fitted to the columnar joint and provided with a plurality of inner circumferential annular grooves communicated with the interior communication flow passage and respective through holes communicated with these inner circumferential annular grooves, the cylindrical joint is connected to the machine frame side so as to form a connection joint of a machine frame side pipe arrangement, and the pipe arrangement block is formed as a connection joint of a boom driving hydraulic cylinder side pipe arrangement.
In accordance with the eighth aspect of the present invention, a plurality of internal communication passages in the columnar joint of the swivel joint mechanism provided at the center of the boom driving hydraulic cylinder hoist supporting point is communicated with a working fluid supply flow passage port provided in the front end portion of the piston rod of the boom cylinder via a plurality of inner communication passages. Accordingly, since it is unnecessary to execute the pipe arrangement extending from the machine frame to the boom driving hydraulic cylinder in an outer portion near the boom driving hydraulic cylinder hoist supporting point, the pipe arrangement is simplified, and an assembling property is improved. Further, since the pipe arrangement is not exposed, a good appearance can be obtained.
In accordance with a ninth aspect of the present invention, there is provided a hydraulically driven type working machine comprises a boom driving hydraulic cylinder, an arm driving hydraulic cylinder and a working tool driving hydraulic cylinder are formed as hydraulic cylinders respectively having communication passages supplying and discharging a working oil fluid from inner portions of respective piston rods to head side oil chambers and bottom side oil chambers in piston chambers within respective cylinders, respective cylinders sides of the driving hydraulic cylinders are respectively connected to the boom, the arm and the working tool side so as to form longitudinally moving bodies, and respective piston rod sides are respectively arranged so as to form hoist supporting points by supporting shaft pins via supporting brackets provided in the machine frame, the boom and the arm side, wherein the hydraulically driven type working machine is provided with a first swivel joint mechanism mounting a boom built-in pipe arrangement to a cylindrical joint and connected to the boom so that the cylindrical joint rotates together with a swing motion of the boom, a third swivel joint mechanism connecting a cylindrical joint to the boom side so as to form a connection joint of a boom built-in pipe arrangement and setting a pipe arrangement block and a columnar joint integrally mounted to the arm side to a connection joint of an arm built-in pipe arrangement, and a second swivel joint mechanism connecting a cylindrical joint to the machine frame side so as to form a connection joint of a machine frame side pipe arrangement and setting a pipe arrangement block and a columnar joint to a connection joint of a boom driving hydraulic cylinder side pipe arrangement, wherein in the hydraulic pipe arrangement to the arm driving hydraulic cylinder, the boom built-in pipe arrangement extending via the first swivel joint mechanism is connected to a front end portion of the piston rod in the arm driving hydraulic cylinder, wherein in the hydraulic pipe arrangement to the working tool driving hydraulic cylinder, the arm built-in pipe arrangement extending via the third swivel joint mechanism is connected to a front end portion of the piston rod in the working tool hydraulic cylinder, and wherein in the hydraulic pipe arrangement to the boom driving hydraulic cylinder, the pipe arrangement block and the columnar joint of the second swivel joint mechanism are integrally connected to the piston rod of the boom driving hydraulic cylinder, whereby the respective hydraulic pipe arrangement to the driving hydraulic cylinders are not exposed to an external portion.
In accordance with the ninth aspect of the present invention, the first swivel joint mechanism at the center of the vertical swing supporting point supplies the oil to one portion in the front end portion of the piston rod having the oil passage extending to the head side oil chamber and the bottom side oil chamber of the arm driving hydraulic cylinder. In this case, the front end portion of the piston rod is connected to a fixed rotation supporting point in the boom side. Accordingly, the pipe arrangement to the arm driving hydraulic cylinder is not exposed to the external portion. Further, the third swivel joint mechanism at the center of the joint connection supporting point supplies the oil to one portion in the front end portion of the piston rod having the head side oil chamber and the bottom side oil chamber of the working tool driving hydraulic cylinder. In this case, the front end portion of the piston rod is connected to the fixed rotation supporting point in the arm side. Accordingly, the pipe arrangement to the working tool driving hydraulic cylinder is not exposed to the external portion. Further, the pipe arrangement block of the second swivel joint mechanism provided at the hoist supporting point of the boom driving hydraulic cylinder and the piston rod of the boom driving hydraulic cylinder are integrally connected to each other. In accordance with these structures, since the pipe arrangements to the respective driving cylinders are not exposed to the external portion, the pipe arrangements do not interfere with an obstacle such as an electric wire, a ceiling of a tunnel or the like during the operation so as to be broken. Further, since the piston rod does not also interfered with the obstacle, it is possible to prevent the piston rod from being damaged.